The latest batch of iPods unveiled by Apple earlier this week are about to begin shipping, and this latest generation brings some pretty big changes across board. The sixth-generation iPod nano looks like something Dick Tracy would wear, the iPod shuffle got its buttons back, and the iPod touch is even closer to being an iPhone 4 without the phone. (Sadly, the iPod classic was excluded from the upgrade party, although it remains—begrudgingly, it seems—in the iPod lineup.)

Having a hard time keeping all these changes straight? We outline what’s new, what’s improved, and what’s missing while tackling all your questions about Apple’s revamped iPod lineup.

The fourth-generation (4G) iPod touch comes in 8GB, 32GB, and 64GB capacities, priced at $229, $299, and $399, respectively. The latest iPod nano—the sixth generation (6G) if you’re scoring at home—is $149 for the 8GB model, and $179 for a 16GB version. It’s also available in all the colors of the rainbow, assuming your version of a rainbow features graphite, silver, pink, blue, yellow, green, and red (as part of the Product Red project). There’s just one capacity of the new fourth-generation iPod shuffle (2GB) and one price tag ($49). But it does come in blue, pink, green, yellow, and silver.

When will the new models be available?

At Wednesday’s press event, Steve Jobs said the new models would each be available next week. For what it’s worth, Apple’s online store lists the ship dates for the assorted iPod models as “1 week.”

Does the iPod touch have a built-in microphone? If so, what’s stopping me from using it as a Wi-Fi iPhone?

Yes, there’s an omni-directional microphone on the back, next to the camera. But even with a built-in microphone, the touch still doesn’t have a speaker just above the top of the display, where you would expect to find one on an iPhone—the speaker is found on the bottom of the iPod touch, to the left of the dock connector port (as you face the iPod’s display). As a result, you won’t be able to hold and speak into a new iPod touch like a traditional phone. But as with the previous iPod touch model, you can plug in a pair of headphones with a built-in mic and place phone over Wi-Fi calls with an app such as Skype. And because the iPod touch now has both a built-in microphone and speaker, it’s possible that you’ll be able to use a VOIP app to make “speakerphone” calls that don’t require a headset.

Can I use the microphone built into the iPod touch’s included headphones?

Given that the iPod touch now includes a built-in microphone and speaker it would make sense for its headphones to include a microphone. Regrettably, not only do the included earbuds not offer a microphone, they also lack the play controls found on some Apple headphones. If you have Apple headphones that do include play controls and a microphone, they work with the new iPod touch.

So what’s new with the iPod touch, then?

The new model is as close to “an iPhone without the phone” as we’ve seen, gaining a Retina display, the microphone, two cameras—one on front and one on the back—and a few other features we’ll get to below. It’s a little bit sleeker than the last generation, measuring 4.4 inches tall, 2.3 inches wide, and 0.28 inches thick (compared to 4.3, 2.4, and 0.3 inches, respectively, for the previous model). It’s also a little bit lighter: 3.6 ounces compared to 4.1.

What are the iPod touch’s camera specs?

As with the front-facing camera on the iPhone 4, the iPod touch’s front camera promises “VGA quality”—that means a resolution of 640 by 480. The rear camera shoots 720p video up to 30 frames per second and captures still photos at the same resolution (960 by 720, or seven-tenths of a megapixel), far lower than that offered by the 5-megapixel rear camera on the iPhone 4.

Does the iPod touch have a camera flash, like the one on the iPhone 4?

Sorry, no.

So does the front-facing camera mean the iPod touch now supports FaceTime?

Indeed it does. That’s one of the marquee features in this generation of the iPod touch, thanks to a new dedicated FaceTime app. Unlike FaceTime on the iPhone 4, however, which up until now has used phone numbers to initiate FaceTime calls, FaceTime on the iPod touch is based on e-mail addresses.

How will FaceTime work on the iPod touch?

When you first launch the FaceTime app on the touch, you’re asked to enter your e-mail address. (You can add more e-mail addresses by entering them in the FaceTime section of the Settings app.) To make a call just open a contact (you can choose contacts from Favorites, Recents, and Contacts screens within the FaceTime app or select a contact within the Contacts app). On the contact’s screen will be a FaceTime button. Tap it to initiate a FaceTime call. Alternatively, if you know that the person you’re calling has an iPhone 4, you can simply tap that phone’s number in the Contact screen and the iPod touch will place a FaceTime call. All you need is a Wi-Fi connection.

What other features does the iPod touch share with the iPhone 4?

As we mentioned above, the touch now features the same Retina display technology you’d find in the latest iPhone, which gives the screen a much-improved resolution of 960 by 640. The touch also features a gyroscope, just like the iPhone 4. Apple likes to tout the iPod touch’s prowess as a gaming device, so these features seem like natural fits and should be welcomed by gamers—the Retina display will mean improved graphics while the gyroscope promises to bolster gameplay.

The new iPod touch also gets an upgrade to 802.11n wireless (from 802.11g in the previous model), but only the 2.4GHz flavor, not the full 5GHz version that Apple uses in its wireless base stations. Oh, and the touch now runs on an Apple-designed A4 chip, which the company says will improve performance and extend battery life to the tune of 40 hours of audio playback and seven hours of video-watching.

Does the iPod touch have a GPS chip?

No. That’s one of the few hardware features still reserved for the iPhone.

Will the iPad Camera Connection Kit work with the Touch?

Sort of. By that we mean that the iPad Camera Connection Kit works with the latest iPod touch just as it does with the iPhone 4. It won’t allow you to import pictures from a camera or media card to your iPod touch, but if you string a dock connector cable between the iPod touch and the connector attached to an iPad, the iPad will recognize the iPod touch as a source for images. The iPad then displays the images on the iPod touch in the Photos app as if the iPod was a camera, allowing you to import those images to the iPad.

What about the iOS 4.1 update?

The iPod touch ships with iOS 4.1. That software update—which is also set to arrive for other devices next week, probably at the same time as the new touch starts shipping—adds a number of features to iOS 4.0. What’s unclear—at least to some of us at Macworld—is whether the update will add AirPlay support to the iPod touch and the iPhone. AirPlay is, of course, the renamed version of the AirTunes technology that let you stream music from iTunes via an AirPort Express. iOS devices will be able to stream music and videos and photos. (Hence, the name change to AirPlay rather than just AirTunes.) Apple’s demo on Wednesday focused on AirPlay in the context of the iOS 4.2 update (which is slated to arrive in November), and while the company mentions AirPlay on its iOS 4.2 Web page, there’s no mention of which iOS gets support on the AirPlay page. Some editors originally thought that AirPlay would appear in iOS 4.1; now, we’re not so sure.

It is worth noting some other changes in iOS 4.1—namely support for Apple's Game Center feature, which should improve the multiplayer gaming experience on mobile devices as well as fixes for some Bluetooth issues with iOS 4.

Speaking of cameras, what happened to the one on the iPad nano?

It’s gone, just a year after Apple introduced it in the previous generation of nanos. The company hasn’t said why—you probably wouldn’t make a big deal out of features you removed from a device, either—but we’re guessing that the nano’s video capabilities never really caught on. Certainly, our tests of the fifth-generation nano found that video quality was acceptable for shooting spontaneous video of family and friends when you were out and about, but that it didn’t measure up to what you could expect from a pocket camcorder. Also, Apple seems to have placed an emphasis on compactness with this iteration of the nano—the latest model is practically all screen and crammed into a 1.48-by-1.61-by-0.35-inch enclosure. It’s difficult to fit a camera into something that compact, so away the camera went.

Well, at least I can still watch videos on the nano, can’t I?

No, that feature’s gone, too. Again, Apple’s not really talking up the features it removed from the nano, but it’s likely a combination of both design changes and product strategy. On the design front, the new nano’s screen is noticeably smaller than what the fifth-generation nano had to offer—the 2.2-inch widescreen display has been shrunk down to a 1.54-inch square. That size and aspect ration aren’t really well-suited to watching the copy of Avatar you rented from the iTunes Store. (Note that the latest iPod nano will display photos and album art, and can even output them, with the right cable, to a TV.) In terms of product strategy, Apple has very clearly drawn a line dividing its mobile devices: If you’re looking for something that will play music, then you can choose either a nano or an iPod shuffle. Anything more—watching videos, using apps, surfing the Web—and you’ll need to upgrade to an iPod touch.

Did the iPod nano lose any other features?

Not as far as we can tell. We’ll keep an eye peeled for any other changes once we get our hands on a shipping version. We can tell you that the iPod nano supports Apple’s VoiceOver technology for announcing artists, songs, and albums. (That’s a feature most prominently on display in the iPod shuffle.) As with past models, this nano supports the Nike+ exercise tracking service, features VoiceMemos and Photo apps, and includes an FM radio.

Does the iPod touch have an FM radio? How about the iPod shuffle?

Only the iPod nano has this feature.

If the nano is basically a screen, how do I control the device?

It’s true that Apple has ditched buttons on the iPod nano (with the exception of physical volume buttons). Instead, the nano now offers touchscreen controls. You navigate the device’s menus and control it by scrolling and tapping, just as you would an iPod touch or an iPhone. You can also control playback using the inline remote control on Apple’s (now-optional) earbuds with remote/mic or any compatible third-party headphones.

Wait, now optional? You mean none of the new models include Apple’s earbuds with the inline remote and microphone?

Sadly, Apple no longer includes its “premium” earbuds—the ones with the inline remote and mic. Instead, the new iPod models include the company’s basic earbuds. For the iPod shuffle, this is likely a fair tradeoff, as the new model regains its physical buttons. But it will present challenges for the iPod nano and iPod touch, especially for those who use these iPods for active pursuits. We’ll have more to say about this once we’ve had hands-on time with the nano and touch.

The iPod nano looks like it’s running iOS. Can I buy apps for it?

The new iPod nano certainly does look like a duck; it features iOS’s telltale square icons and a handful of multi-touch gestures. But the new nano does not actually walk like said duck—it’s not running iOS.

What changed with the shuffle?

The main change is the device’s design: as mentioned above, Apple has ditched the buttonless look of the previous model and returned to physical playback controls. Don’t worry about those buttons adding bulk to the shuffle, though—at just 1.14 inches tall, 1.24 inches wide, and 0.34 inches thick, the new shuffle is still fairly compact. In fact, it’s noticeably smaller than the second-generation shuffle, which sported the same controls.

So do the buttons mean that the shuffle no longer features VoiceOver and playlist support?

No, those features have been retained. In fact, the latest shuffle offers a dedicated VoiceOver button to make the feature more accessible. However, as noted above, you do lose the inline remote control on the earbuds.

What about the iPod classic? Apple didn’t mention a thing about that model this week.

Oh, you noticed that? It was a conspicuous omission, especially given that Steve Jobs told the audience at Wednesday’s event that every iPod model had been updated. That would seem to imply the classic’s time as the last hard drive-based iPod model is up. Yet, the classic still has its own promotional page on Apple’s Website and you can still buy that model from Apple’s online store. (It’s the same $249 160GB classic, available in either black or white, that Apple introduced last year.) What’s unclear is if Apple is just going to continue selling the classic until it runs out of inventory or if it’s keeping the classic as a part of the product line for customers who want a high-capacity music player. We put in a call to Apple’s PR department to get an answer to that question, but we have yet to hear back.

This article was updated on September 5 to correct our answer on the question about iOS 4.1.

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